title: Rapid determination of silver in nanobased liquid dietary supplements using a portable X-ray fluorescence analyzer.
abstract: This paper reports a rapid and straightforward method for the quantitation of total Ag content in nanobased commercially available liquid dietary supplements using a portable X-ray fluorescence (pXRF) analyzer. Figures of merits were evaluated by analyzing a series of AgNO3 standards. This method was shown to have a detection limit of 3 ppm, a quantitation limit of 10 ppm, and a broad linear range from the detection limit to 10000 ppm (1%). Accurate detection and quantitation of Ag content in well-characterized Ag nanoparticle samples and in nanobased liquid dietary supplements were achieved with good correlation (i.e., percentage difference average values under 15%) between the total Ag concentration obtained by the pXRF analyzer and by inductively coupled plasma mass spectrometry (ICP-MS). Furthermore, accurate quantitation of Ag in the presence of high concentrations of potential spectral interferences was also demonstrated.
authors.affiliation: Office of Regulatory Affairs, Arkansas Regional Laboratory, US Food and Drug Administration, Jefferson, Arkansas 72079, United States.
authors.forename: Germarie
authors.initials: G
authors.lastname: Sánchez-Pomales
authors.forename: Thilak K
authors.initials: TK
authors.lastname: Mudalige
authors.forename: Jin-Hee
authors.initials: JH
authors.lastname: Lim
authors.forename: Sean W
authors.initials: SW
authors.lastname: Linder
mesh_terms: D019587:Dietary Supplements / Q000032:analysis*; D057230:Limit of Detection; D012834:Silver / Q000032:analysis*; D013052:Spectrometry, X-Ray Emission / Q000295:instrumentation / Q000379:methods*
chemical_list: D012834:Silver